1tf1

From Proteopedia

---

Revision as of 01:05, 21 November 2007

proteopedia linkproteopedia link

spinqualitylabelsall models 1tf1, resolution 1.80Å Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image

Crystal Structure of the E. coli Glyoxylate Regulatory Protein Ligand Binding Domain

Overview

The interaction of Escherichia coli AllR regulator with operator DNA is, disrupted by the effector molecule glyoxylate. This is a general, yet, uncharacterized regulatory mechanism for the large IclR family of, transcriptional regulators to which AllR belongs. The crystal structures, of the C-terminal effector-binding domain of AllR regulator and its, complex with glyoxylate were determined at 1.7 and 1.8 A, respectively., Residues involved in glyoxylate binding were explored in vitro and in, vivo. Altering the residues Cys217, Ser234 and Ser236 resulted in, glyoxylate-independent repression by AllR. Sequence analysis revealed low, conservation of amino acid residues participating in effector binding, among IclR regulators, which reflects potential chemical diversity of, effector molecules, recognized by members of this family. Comparing the, AllR structure to that of Thermotoga maritima TM0065, the other, representative of the IclR family that has been structurally, characterized, indicates that both proteins assume similar quaternary, structures as a dimer of dimers. Mutations in the tetramerization region, which in AllR involve the Cys135-Cys142 region, resulted in dissociation, of AllR tetramer to dimers in vitro and were functionally inactive in, vivo. Glyoxylate does not appear to function through the inhibition of, tetramerization. Using sedimentation velocity, glyoxylate was shown to, conformationally change the AllR tetramer as well as monomer and dimer, resulting in altered outline of AllR molecules.

About this Structure

1TF1 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.

Reference

Structural and biochemical study of effector molecule recognition by the E.coli glyoxylate and allantoin utilization regulatory protein AllR., Walker JR, Altamentova S, Ezersky A, Lorca G, Skarina T, Kudritska M, Ball LJ, Bochkarev A, Savchenko A, J Mol Biol. 2006 May 5;358(3):810-28. Epub 2006 Mar 3. PMID:16546208

Page seeded by OCA on Wed Nov 21 03:12:39 2007